This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a Phase I protocol to evaluate the safety and tolerability of JVRS-100, a cationic lipid DNA complex (CLDC), for the treatment of patients with relapsed/refractory leukemia. This currently has a dismal prognosis. JVRS-100 consists of complexes of cationic lipid and plasmid DNA without a gene insert (non-coding DNA) which are potent activators of innate and adaptive immunity, induce NK, T and B cell activation, and stimulate the secretion of interferon-[unreadable], interferon-[unreadable], IL-12 and other cytokines. This is a 2 stage Phase I trial. In stage 1, an accelerated titration schema will be followed with one patient at each dose level. Stage 2 will commence after a dose limiting toxicity (DLT) is observed in stage 1 or after the maximum dose for stage 1 is reached. Stage 2 will follow a modified Fibonacci schema with 3-6 subjects at each dose level until a Recommended Phase 2 Dose (RP2D) is determined. The cohort will then be expanded to a maximum of 12 patients to more fully evaluate the RP2D.